Hollow glass items may be manufactured using several methods.
One of these methods consists of depositing at least one drop of glass, also called a paraison, in a cavity of the mold. This cavity has an inner shape that corresponds substantially to the outer shape of the item.
Then, a punch is inserted into the cavity of the mold so as to give the item substantially its final shape.
As an example, the item may have a rectangular or square outer shape and a conical inner shape by using the punch.